1. Field of the Invention:
This invention relates to a photographic camera of the kind permitting selection of one of various exposure control modes and more particularly to an exposure control mode selection device which gives a warning when the desired picture image effect corresponding to a selected exposure control mode is difficult obtain.
2. Description of the Prior Art:
As a result of recent advancement of electronic applications in photographic cameras, multi-mode automatic exposure control type cameras, which permit switch-over among various exposure control modes by a selecting operation on an operating member, have been in practice. In regard to pictographs or the like for displays made on photographic cameras on the other hand, cameras using pictographs of mountains or dolls as an indication of distance for visual distance measurement have also been in practice. Use of patterns for indicating flash photography has also been in practice.
However, in exposure control display modes. letters or symbols have been used. In many of the above-stated multi-mode, automatic exposure control cameras, the exposure control modes are indicated by letters or symbols such as M (for manual), AV (for aperture preference AE), TV (for shutter preference AE), P (for programmed AE), etc. With this conventional arrangement, it is difficult to be understand what is indicated by such letters or symbols, particularly for beginners. Beginners are incapable of selecting an adequate aperture value or shutter time suitable for obtaining a desired picture image effect. The image effect varies with the focus depth and shutter time. For people who do not know the interrelation between an aperture value, shutter time, film sensitivity and brightness of an object to be photographed, the relation of a picture effect to the aperture value and shutter time is difficult to understand. Therefore, a mere indication of the exposure control mode in letters or symbols does not let such people readily know an appropriate combination of the shutter time and the aperture value required for obtaining a certain desired picture effect. Besides, the prior art indication can not show a photographing range within which an adequate picture image effect is obtainable. For example, with a symbol A or AV used for indicating an aperture preference mode, it is still unknown what the aperture value should be in order to obtain a pan-focus effect, which gives a photograph with a deep focus depth and which is obtainable by making the aperture smaller. It is also unknown at what range of object brightness the pan-focus effect can be obtained.
To solve this problem, the present inventors have previously proposed an arrangement as disclosed in Japanese Utility-Model Application No. Sho 55-154016 corresponding to U.S. patent application Ser. No. 313,504. According to the proposed arrangement, in order for a beginner to take a photograph considering the picture effect obtainable from a combination of aperture value and shutter time, the camera incorporates therein a program of combinations of aperture values and shutter time values from which various picture effects are derivable. Simple pictographs representative of picture effects obtainable in accordance with the program are shown within a view finder or on the surface of the camera. The simple selection of one of the various pictographs shown on the camera surface enables the photographer to take a photograph with the picture effect represented by the selected pictograph.
It is an object of the invention to provide an improvement on a camera permitting the photographer to obtain a photograph having a desired effect represented by a pictograph with the pictograph selected out of various pictographs. The improvement gives a warning when the desired picture effect cannot be obtained.
It is another object of the invention to provide an improvement on a camera permitting the photographer to obtain a photograph having a desired effect represented by a selected pictograph, the improvment displaying all exposure control modes selectable from various exposure control modes depending on the brightness of the object to be photographed.
These and further objects and features of the invention will become apparent from the following detailed description of preferred embodiments taken in conjunction with the accompanying drawings.